Electrode structure for generating ions of one or other polarity commonly rely upon a point emitter to establish an intense electrical field about the point sufficient to form ions in response to an applied ionizing voltage. However, ions generated in this manner for delivery within a flowing stream of air or other gas are significantly immobilized by the intense electrical field and may be poorly delivered into the flowing stream.
Long, thin wire electrodes are known for generating ionizing electric fields over linear dimensions, for example, for delivering ions of one polarity to a closely-spaced charging object such as an imaging drum of an xerographic printing device. However, an ionizing electrode of this type is usually mounted very close to the charging object and in tension over the span of its length to assure reasonably accurate spacing between the wire electrode and imaging drum.